Thread feeding device and process



United States Patent it [72] Inventors KennethJ-Rupprech l16-127;28/72A,72A(3);66/l25, 125A. 132,

134 [56] References Cited UNITED STATES PATENTS 2,60l ,451 Page 28/72A(3) 2,857,651 10/1958 Keen 28/72A(3) Primary Examiner-Henry S. Jaudon Attorney- Robert Ames Norton ABSTRACT: Looms are fed with a thread or yarn from a tubular knitted tube of the yarn with thread unraveling from its end and hence under insignificant back tension. The tube can be pulled up by the pull on the yarn or preferably a portion is advanced to avoid any back tension. When the yarn has been unraveled from the length of tube advanced, another short length is advanced.

A preferred form of advancing mechanism is described in which the yarn tube moves between ametallic finger and a conducting surface. When the predetermined length of tube is advanced it insulates the two contacts and no further advancing takes place until the yarn from the tube has been unraveled back to the point where the finger contacts the conductive surface. This starts a motor turning two rolls which advance a certain length of tube and the motion of the roll ceases when a cam on the shaft of one of the rolls opens a microswitch. The advanced portion of the tube remains until it has again been unraveled back to the point where the contact is made as described above.

The feed is useful for any types of looms which obtain part or all of their weft threads from an external source. Typical examples of this type of loom are looms which use gripping or bullet shuttles and catch thread looms. Similarly most knitting machines draw their yarn or thread from an external source and the described stocking feed is useful on such machines 7 also.

. .Patgmed No 24, 1970 3,542,084

r 1 Sheet 1 or? INVENTOR. KENNETH J. RUPPRE C H T ALBERT-[RICHARDS ATTORNEY Patentcl Nov. 24, 1970 3,542,084

Sheet 2 of2 M0 roR' C2 LMMJ ' a l5) /2 v M/CRO SWITCH RELA r- /7 E INVENTOR. KENN TH .1. RUPPRECHT F:- g" ALBERTJR/CHARDS ATTORNEY There area nuniberof fabric making machines which receive thread or yarn'from anexternal'sour'ce or, in some cases-several external sources; Typical examples are looms which use gripping or bullet shuttles, such as forexample the looms described in the Pfarrwaller Pat. Nos. 2,589,429 and 3,076,483; catch thread looms, such as described in the Fischer Pat. No. 671,820; and most knitting machineslln each case the thread or yarn is supplied from an external source and not from thequill in a shuttle, as in the ordinary type of shuttle loom. it will be noted that in a catch thread loom, while there is a shuttle with a quill, the thread or yarn from the quill serves only to catch and pull across double'picksof an externally supplied thread in the form of a loop. The amount of thread from the shuttle is a minute portion of the ,total length of weft thread, serving only to pull the weft across and to'bind one or more edges of theresulting'fabric.

In all of the machines'referred to, thefeed of the thread from an external source presents a problem. It is usually desirable that the thread be fed'under uniform and preferably quite low back tensiongwith hard threads or yarns which are substantially inelastic, the problem is not too serious, and yarn wound on cones or in packages has been practically used. However, when dealing with certain other types'of yarn,such as for example elastic yarn, and especially core spun'elastic yarn in which the elastic core is spun with stapleor filament,

yarns which are soft, bulky, and fluffy, and other similar types of yarn, they are not conveniently handled in the ordinary yarn packages. For example, with elastic yarns, and especially core spun elastic yarns, either the yarn has to be wound'on a relatively soft packageor wound on a hard bobbin under con- "siderable tension. In either case a serious problem results,

especially when-the yarn packages or other form in which they are wound cannot be fed to the fabric making machines immediately or very shortly after winding'lf there is considerable storage, elastic yarnstend to'take, a permanent set, which is not uniform ifthey' are wound tightly, orthCY may. shrink and. distort relatively soft yarn packages, which presents problems of nonuniform tension, snarling, and the-like when the'yarn'is fed to the fabric making'ntachine.

Even with hard, inelastic textile yarns, problems are presented when the yarn has to be dyed in different colors. Unless the yarn is dyed carefully in skein form and thenwoun'd into packages, uniformity of dyeing often suffers. For example, in a package wherethe yarns cross over each other a dye bath may not bathe the yarn uniformly at such points andthis may result in the so-called crossoverproblem, where the dyeing at these points is not as deep as in theremainder of the yarn. It is normally considered economically -very ad vantageous to dye yarns in package form. However, in a number of cases, as pointed out above, this raises problemsof uniformity. and the like; Another problem which, though not as serious, is still a drawback in fabric making results when a some cases, can be knitand the tube is readily shipped. 0rdinarily the shipping is in boxes in which the tube is folded, and asone end is pulled out the tube unfolds for the next fold. The cost of knitting the tube is quite low as knitting can proceed at very fast speed because precision knitting is not even if the yarns are elastic yarns, such as core spun yarns, and the problems of excessive permanent set or distortion of soft packages are not encountered. Also, dyeing of the knit tube can be effected very economically and with a high degree of uniformity. Thus even with threads or yarns of hard textile fibers, which could be fed from packages, the advantages of dyeing are still retained. It should be noted that with certain yams-the temperature of dyeingmay, be sufficiently high to ef fect some heat setting of the yarn. Therefore, even in the case of yarns which could be practically fed from the customary bobbins or'packages, the present invention presents advantagesin quality and, in many cases, in cost of dyeing. As a result, even in the case of such yarns, the present invention is often advantageous and is included in a broader aspect of the present invention. Of course from the standpoint of apparatus, the feeding mechanisms'are not ordinarily concerned with the exact nature of the yarn fed, and even in theprocess aspect of the present invention the broader claims are not to be considered as limited to special types of yarns which are difficult or impossible to feed satisfactorily without using the present invention. However, in more specific aspects such yarns are included and there the advantages of the present invention are most marked.

cient to' pull up the tube from its container, and only rudimentary precautions of rollers or other guide means are needed in such a case. However, in some cases this can result in the tube being pulled out faster than the fabric forming machine is using the thread unraveled from the end thereof, and this can cause the tube to jam or the unraveled thread to snarl. This is particularly likely to happen with elastic threads which are not very smooth, such as for example core spun elastic yarn. Therefore, in a preferred and more versatile form of the present invention,- means are provided to feed a short predetermined length of the tube, the feedingmeans being controlled or a feeding cycle initiated by the unraveling of the tube backto a certain point. This insures that there isno number ofdifferent colorsor textures of yarn are to be used in.

the same fabric; for example, if there are to be a number of different weft threads, either of different colors, different textures, or both, packages on which'yarnjrnay be wound can be somewhat bulky, and the space. taken sometimes creates problems. 'It is true that the packages may be situated at quite a distance from the point wherethe yarnsare actually fed into the fabricmaking machine, but this requires. the unwound yarn to travel over a considerable distance, increasing the pos-.

sibilities of snarling, nonuniform tension, and the like.

SUMMARY, OF THE INVENTION Essentially, the present inventionjforms the yarn or thread to be fed tothe fabric making machine in the form ofa knitted tube. When the end of the tube is presented to the fabric making machine, the thread or yarn is unraveled from the end under perfectly uniform and relatively low tension. The tube is a compact form in which a very long length of yarn, miles in chance of the tube getting away from the feed and being pulled out' too fast andassures against malfunction even with the most difficult yarns to be handled. Because, as will be described below, very simple, reliable and cheap feeding mechanisms are possible, it is often desirable to utilize the preferred modification even with tubes of yarn which could be.

handled without the specialperiod feeding of predetermined lengths of tube. In its broadest aspects, of course, the present invention is not limited to the preferred modification, but in more specific aspects this is included. I

lt'will-be obvious that the present invention does not require in all cases that the mechanism for feeding the tube, or'

presenting an edge to be unraveled at the proper point, be a permanent or fixed part of the fabric making machine. On the contrary, the feed may ,be portable and moved from one machine to another. Such a portable form will be described in more detail below, but of course the invention is not limited to it and, strictly speaking, from the standpoint of the fabric making machine, which is being fed yarn from the unraveling of the end of a tube, it makes no difference to the machine whether the tube is presented at the proper point by mechanisms which are a fixed part of the machine or which are portable. v

The advantages of dyeing in tube form, which have been mentioned above and which make the present invention of particular importance with yarns which have to be dyed, also permit readily and cheaply certain special effects which are not so readily achieved or so economically achieved with yarns dyed in skein or continuous form. Certain special fabrics require a variegated effect, that is to say, the thread may be dyed different colors or different shades of the same color which vary periodically along the thread to produce in the fabric a special variegatedpattern. It is comparatively easy to dye these variegated shades in tube form, and so this special type of yarn or fabrics made therefrom constitute a field in which the present invention presents important advantages.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. I is an isometric view. diagrammatic in nature, of a loom with a feeding mechanism according to the present invention;

FIG. 2 is a top elevation of the feeding mechanism;

FIG. 3 is a side view of the mechanism; and

FIG. 4 is an electrical diagram of the feeding mechanism.

DESCRIPTION OF THE PREFERRED EMBODIMENT In FIG. 1 the preferred form of tube feeding mechanism is shown, with the automatic feeding eliminated in order to avoid confusion in the drawing, the feeding mechanism being shown in FIGS. 2 and 3. Warp threads 1 from a suitable beam 2 pass through two sets of heddles 5 and 6, which in the conventional manner produce alternating sheds, and the woven fabric 3 is finally taken up on the take up roll 4. The loom is shown diagrammatically in order to avoid confusing the drawings with details which are not changed by the invention. A bullet shuttle is shown at 7 which catches the weft thread 8 in the normal manner. This thread or yarn ravels off from the end of a tube and is under uniform and generally negligible tension. g

The tube is foldedin acontainer 16, which constitutes a feed reservoir, and passes up over a guide roll 9 between two feed rolls II. In FIG. I the details of controls of these rolls are not shown, but in FIGS. 2 and 3 they are set forth. It will be seen in FIG. 3 that the tube 10 passes between a metallic bracket 13 which is grounded, and a finger 12 is connected to the other side of a low control voltage, as can be seen in the wiring diagram in'FIG. 4. When the tube is between the finger I2 and the bracket 13, it acts, of course as an insulator and so, as can be seen from FIG. 4, the motor driving the rolls 11, (not shown in FIGS. 1 to 3), does not turn. As the loom operates, the loom shuttle 7 pulls successive lengths of the thread or yarn 8 through the sheds as they are formed to produce the conventional picks.

As the thread unravels from the end of the tube 10, presently a point is reached where the tube is no longer between the finger 12 and the bracket 13. The finger then drops by its own weight, contact is made through a relay 17, (FIG. 4), and the feed rolls 11 turn, advancing a portion of the tube, which lifts up the finger 12. However, as the relay 17 is a normal locking relay, the rolls 11 continue to turn until a full turn causes a cam 14 on the shaft of one of the rollers to open a microswitch 15. This is clearly shown on FIG. 3. The microswitch unlocks the relay 17 in the conventional manner for a locking relay and the rolls stop. The continued operation of the loom then continues to unravel the thread 8 from the advanced end of the tube until once again the tube is unraveled past the finger 12, when the sequence of operations described above is repeated.

It will be seen that since there is no significant back tension from the unraveling of the tube, it is a matter of indifference exactly how long a piece of tube is advanced, and it is unnecessary to-provide a precise synchronous drive with a loom drive. Without intendingto limit the invention in any way, a

typical loom operation may result in advancing about 3 inches of tube at a time. 7

It will be seen that the tube feeding mechanism is extremely simple and compact, and in the case of looms or other machines requiring more than one kind of yarn, for example yarns of different colors, several feeding mechanisms may be arranged side by side orin any other configuration so that the tubes of the different yarns are presented at the proper points to the fabric making machine. The loom illustrated in FIG. 1 is in purely diagrammatic form, showing only the elements necessary to an understanding of the feed of yarn which forms the subject matter of the present invention. The means for moving the shuttles 7, beating up picks and the like are not shown as they are in no way changed by the present invention. The loom is, of course, also typical only of one type of fabric making machine, and the invention is applicable to any such machine which utilizes yarn or yarns from an external source. for example, a catch thread loom, knitting machine, and the like.

The more specific modifications of the present invention can use any mechanism for advancing periodically a length of tube. The electrically controlled advancing mechanism which is illustrated in the drawings is simple, reliable and cheap, and may be considered a preferred form of the present invention. However, any other means may be used. For example, the amount of tube fedmay be controlled by electric eyes or by any other means which stops the advance after the desired amount has been obtained.

Where the yarns are of suitable types, it is possible to use a simplified feed mechanism in which the rolls I1 and their drives are eliminated, the tube being pulled up from its supplying container by the pull of the yarn 8 as it is unraveled. This simplified feed mechanism does not give as great protection against pulling out the tube too fast and possible snarling. Therefore, for many purposes the preferred specific modification which is shown in the drawings will be advantageous and, of course, is more versatile, as it can be used with yarn having characteristics such that the simplified mechanism would not be suitable.

We claim: p

1. A mechanism for feeding yarn to a fabric making machine utilizing at least one yarn from an external source, which comprises:

a. an external source suitable for storing a continuous,

folded, knitted tube of the yarn to be used; and

b. means for feeding an end of the tube to a point on the fabric making machine where yarn is to be supplied, said means advancing predetermined lengths of tube to the point adjacent the fabric forming machine, the advancing means being provided. with means forstarting the advancement when the tube has been unraveled to a predetermined point and for stopping the advancement after the predetermined length of tube has been advanced whereby the yarn is unraveled from the tube as the fabric making machine operates and uses the yarn, whereby the fabric making machine receives yarn feed at uniform low tension. 2. A mechanism according to claim 1 in which the tube passes between electrical contacts, one of which is movable,

I whereby the tube insulates the contacts until the tube has been unraveled back to the point where the contacts can close, and means for advancing tube actuated by the closing of the contacts, said advance means being provided with stopping means after a predetermined advance.

3. A mechanism according to claim 2 in which the advancing means comprises a pair of rolls, an electric motor for driving them, contacts between which the predetermined length of tube moves, one of the contacts being movable by gravity to close a circuit with the other contact when the tube is unraveled back to the predetermined length, locking relay means t 4. A mechanism according to claim}; in which the relay unlocking and resetting means comprise a cam on a shaft turned by the motor and a microswitch cooperating therewith to unlock and resetthelockingrelay means. a 5. A processfo'r feeding a fabric making machine with-at least one externally supplied yarn; which comprises presenting 9 to the machinea knitted tubular tube of the yarn tobe-used by the machineby advancing-a predetermined lengthf'of tube, permitting the machine to feed itself yarn unraveled from the end of the tube andrepeating the advancing of the tube when the unraveling of 'the'yarn has unraveled the predetermined 

